The 16-year-old, competing for Italy, smashed his lifetime best to make the podium in the 200m butterfly event at Toll Cross.
He clocked a stunning time of 1:55.97, which was not only a new personal best but also a new Italian junior record. It was also more than a second faster than he had swam in the semi-finals.
Burdisso thought he had just missed out on making his first senior international final when he clocked 1:57.20 in the semis. That ranked him ninth overall, with only the top eight progressing.
But Great Britain’s James Guy withdrew from the race to concentrate on the 4x200m freestyle relay which was just after the individual butterfly final.
Burdisso was first reserve and he took his chance. He was second all the way through the race until just getting pipped in the closing stages by Hungarian Tamas Kenderisi, who took silver behind his team-mate Kristorf Milak.
Afterwards the Mount Kelly pupil, who became the first person born after the year 2000 to win an international swimming medal for Italy, said: “I knew I had nothing to lose. I went into the final without too much pressure: the medal is really unexpected. Now the next target is the Italian record.”
Meanwhile, two former Plymouth College pupils were among the medals in Glasgow on Sunday.
Ruta Meilutyte, who famously won an Olympic gold medal as a 15-year-old at London 2012, took silver in the 100m breaststroke.
The 21-year-old, who swims for Lithuania, clocked 1:06.26 to finish behind controversial Russian Yuliya Efimova, who has twice failed drug tests.
The evening ended with ex-Plymouth College pupil Calum Jarvis helping the Great Britain men’s 4x200m relay to gold.
Jarvis swam the first leg before passing on to Duncan Scott, with Thomas Dean and James Guy completing the winning quartet.